Veterinary research in horses encompasses the study of diseases, health management, and medical treatments specific to equine species. This field investigates various aspects of horse health, including infectious diseases, metabolic disorders, and musculoskeletal conditions. Researchers focus on understanding the pathophysiology of equine ailments, developing diagnostic tools, and evaluating therapeutic interventions. The study of horse health also involves examining preventive measures such as vaccination protocols and nutritional management to promote overall well-being. This page collects peer-reviewed research studies and scholarly articles that explore the diverse areas of veterinary science related to horses, providing insights into disease mechanisms, treatment strategies, and advancements in equine healthcare.
Parry BW, McCarthy MA, Anderson GA.Resting coccygeal blood pressure values were measured, indirectly, on 296 horses (97 Thoroughbreds, 97 Standardbreds and 102 hacks). Blood pressure was found to vary with the class of horse examined; on average Thoroughbreds had significantly higher values than Standardbreds and hacks, whereas blood pressures of the last two groups were not significantly different. There was no demonstrable effect of sex, height or heart rate on blood pressure, but temperature and age did influence the value recorded. Mean (+/- sd) (n = 296) coccygeal uncorrected values (systolic pressure/diastolic pressure) w...
Kleider N, Lees MJ.The investigation of a chronic, seasonal dermatitis of horses in southwestern British Columbia is described. Typically the history indicated an insidious onset, followed by a gradual progression in the severity of the signs each year. Lesions appeared during the warmer months of the year and tended to regress during the winter. The clinical signs consisted of areas of pruritus and excoriation, affecting predominantly the ventral midline, mane and tailhead. In all cases corticosteroid therapy relieved the pruritus and allowed the lesions to heal.The salient pathological findings were hyperkerat...
McIlwraith CW.This paper reviews the current status of diagnostic and surgical arthroscopy in the horse. Arthroscopy has been used as a diagnostic aid since 1974 and is useful for evaluation of abnormalities in synovial membrane and articular cartilage. Surgical arthroscopy is a more recent advance that has replaced conventional arthrotomy in 90 per cent of the author's cases. Clinical conditions currently being treated using arthroscopic techniques rather than arthrotomy include all chip fractures in the carpus, chip fractures of the first phalanx, chronic proliferative synovitis in the fetlock and osteoch...
Badoux DM.The ratio between the length of the anterior and posterior cruciate ligaments and the distance between their femoral and tibial attachments in the canine and equine knee joint reveals that these structures form a Tchebychev mechanism for parallel motion.
Sławomirski J, Flieger S, Jastrzebski M, Boratyński Z.The studies carried out on 2 spinal cords of horses showed that cells of the medial motor nucleus (nucleus motorius medialis) are present in all neuromers of the lumbar and sacral segment of the spinal cord. It lies in the medial part of grey matter of the ventral column, neighbouring laterally and ventrally with cells of the lateral motor nucleus, whereas dorsally with cells of the nucleus of the ventral commissural horn. Along the nucleus numerous constrictions and intervals are found, which are connected with various numbers of nerve cells in particular cross-sections.
Holt PE, Pearson H.The presenting signs, treatment and postoperative progress of 13 horses with vesical and urethral calculi are reviewed. Single, discrete stones were present in 10 animals in which the results of treatment were generally good. In three horses with sabulous cystic deposits, urolithiasis was associated with bladder paralysis and the response to treatment was poor.
Hopfer SM, Van Kruiningen HJ, Daniels WH.Twelve horses were divided into three groups and given various doses of a mixed species strongyle inoculum, representing light, moderate, and heavy infections. Three weeks after the larval inoculations, three animals from each group were given larvicidal doses of thiabendazole (TBZ) (440 mg kg-1 on two consecutive days); one animal from each group served as a non-medicated control. Treatment was repeated three weeks later. One treated animal from each group was designated for long-term study; others were necropsied to study adult and larval parasite loads. Six of the twelve animals with strong...
Perryman LE, Wyatt CR.Equine lymphocytes incubated with Con A and isolated on discontinuous BSA density gradients suppressed mixed lymphocyte reactions in a cell dose- and Con A dose-dependent manner. Suppressor lymphocytes were radiosensitive, even after the initial Con A incubation phase was completed. Suppressor activity was consistently demonstrated using peripheral blood mononuclear leukocytes from normal horses, but was absent in thymus cells and variably present in lymph node cells. Suppressor lymphocytes were present in horses with selective IgM deficiency, and within neoplastic lymph nodes from a horse wit...
Klei TR, Torbert BJ, Chapman MR, Turk MA.A controlled test method was used to evaluate the efficacy of injectable micelle and oral paste formulations of ivermectin (22,23-dihydroavermectin B1) against 8-week-old Strongylus vulgaris larvae in experimentally infected pony foals. The dosage level of the drug in both formulations tested was 0.2 mg/kg. Ponies were euthanatized and necropsied 5 weeks after treatment. Based on the recovery of live vs dead S vulgaris from mesenteric arteries, both formulations were greater than 99% effective. Increased weight gains and marked reductions in the severity of arterial lesions were observed in tr...
Leach DH, Oliphant LW.Annular gap junctions interiorized within cells of the stratum spinosum of the coronary border of the equine hoof were degraded by two methods. Some were autophagocytized and some appeared to fuse with lysosomes to form heterophagosomes. Structural changes of partially degraded annular gap junctions included increased density of the enclosed cytoplasm, formation of filamentous or membrane-like material within the annular gap junction, and disruption of the circular or oval profile of the gap junction. The annular gap junctions are apparently incorporated into the fully keratinized cells of the...
Dewey EA, Maylin GA.The metabolism of propionylpromazine in the horse was studied. Although propionylpromazine is not currently approved or recommended for use in horses, it has been used illegally to alter their performance. Propionylpromazine hydrochloride was administered intramuscularly at clinical and subclinical doses. Three metabolites were detected in urine. The major metabolite was identified as 2-(1-hydroxypropyl) promazine sulfoxide. The detection of this metabolite in routine drug testing has been described.
Frost ML, Colton SW, Wertz PW, Downing DT.The C34, C36, and C38 dienoic omega-lactones were isolated from sebum of the horse (Equus caballus) and the double bond positions were determined by stepwise chemical dissection and analysis of the fragments. The structures found could be formed by delta 9-desaturation at the C18-stage of fatty acid biosynthesis followed by a second delta 9-desaturation when the chains reached C24, C26, C28, C30, or C32 and then addition of one to seven 2-carbon units. These findings provide insight into the dimensions and organization of the endoplasmic reticulum in cells of the sebaceous glands.
Johansson IM, Schubert B.Flunixin is determined in equine plasma by liquid chromatography on LiChrosorb RP-18 with 70% methanol in phosphate buffer pH 3.1 as the eluent, with detection at 284 nm. Plasma is deproteinized with methanol and the supernatant is then injected directly into the system. With a short pre-column (5 x 3 mm i.d.), which is replaced after 25-40 injections of sample, 420 plasma samples could be analysed on one analytical column. The detection limit in plasma is 0.30 micromol/l (89 ng/ml) and the method can be used in pharmacokinetic studies.
Westermarck E, Lindberg LA, Sandholm M.A sensitive gel-diffusion assay for determination of phospholipase A was developed. PLA standards, serum, faecal and pancreas homogenate samples with PLA-activity were allowed to diffuse from wells into agar-gels containing lecithin-membranes. The turbidity cleared radially upon PLA-activity. The diameters of the cleared zones showed a linear relationship with the log of the enzyme concentration. Serum samples resulted in some turbidity within the cleared zones. This interference originating from serum lipoproteins could be abolished by hydrophobic absorption. The gel-diffusion method was comp...
Hilbert BJ, Rowley G, Antonas KN.A method previously described was used to determine the hyaluronic acid concentration in synovia from normal and arthritic horse joints. The concentration of hyaluronic acid in the synovia from arthritic joints was found to be significantly lower than the concentration in fluid from normal joints.
Stratil A, Tomásek V, Bobák P, Glasnák V.Homozygous horse transferrin (Tf O) is highly heterogeneous. In starch gel electrophoresis it gives at least 9 zones. Two main components (2a and 4b) were purified by rivanol and ammonium sulphate precipitation, DEAE-Sephadex chromatography and SP-Sephadex chromatography. Molecular weights of 75 200 and 80 500 for components 2a and 4b, respectively, were determined by sedimentation equilibrium ultracentrifugation. Amino acid compositions of the two components were similar, and there were no differences in the N-terminus (glutamic acid followed by glutamine) and the C-terminus (valine). Differe...
Metenier L, Grosclaude J, Meriaux JC.The chief application of blood typing in domestic animals is in the verification of parentage. However, the acquisition of good standardized reagents in sufficient quantity remains an obstacle for the development of this work. The production of monoclonal antibodies directed against blood group determinants offers an attractive means of improving both the quality and quantity of serological reagents, and could facilitate the definition of new specificities. Fusions between a mouse myeloma line and splenocytes from mice immunized with horse red cells have resulted in four hybridomas producing a...
Pfeil L, Zetner K.A mare with rectal prolaps was operated at Vienna University. The prolaps was corrected by mucosal resection only. The remaining vital layers of the corresponding intestinal section were saved. The advantage of a special tissue saving operating technique in the rectal area is seen in avoiding postoperative complications.
Dipeolu OO, Adeyefa CA.Ticks of the species Amblyomma variegatum (Fabr.), Boophilus decoloratus (Koch), Boophilus geigyi Aeschl. et Morel, and Hyalomma rufipes Koch were detached from cattle, sheep and horses and the influence of these various hosts on the biology of ticks was investigated. No A. variegatum was found in horses. The parameters studied were preoviposition and oviposition periods, ovipositional capacity, eclosion period, hatching patterns, egg sizes and temperature effect. Although the preoviposition and eclosion periods were similar in each tick species irrespective of the host from which the adults w...
Antczak DF.A new polymorphic locus of the horse which has several unusual properties is described. The suggested name for the locus is ELY-2. The gene product of one allele at this locus, designated ELY-2.1, has been identified with antisera raised as a result of pregnancy. Antibody to ELY-2.1 was first detected on day 55 after conception in the serum of a mare in first pregnancy. This early onset of antibody is similar to that seen for antibody to ELA antigens, and suggests that the source of the antigenic stimulus may be the tissue of the equine endometrial cups. The antisera identifying ELY-2.1 are cy...
Evans KS, Carpenter SL, Sevoian M.The enzyme-linked immunosorbent assay (ELISA) antigen-positive and agar-gel immunodiffusion test (AGID)-negative horses do not have infective equine infectious anemia (EIA) virus. The ELISA testing of horse leukocyte culture (HLC) supernatants did detect EIA virus in a HLC that was infected with the Wyoming strain of EIA virus and in HLC derived from horses in febrile, acute, or subacute stages of EIA infection. In supernatants of HLC derived from chronic and inapparent carrier horses, EIA virus was not detected with ELISA. Direct fluorescent antibody tests detected EIA virus in HLC infected w...
Jørgensen RJ, Andersen S.Between 10 and 25% of the Dictyocaulus arnfieldi larvae excreted in faeces from a naturally infected donkey were harvested as infective stages from faecal cultures by means of Pilobolus fungi. The faeces were collected between 24 and 56 hours after drenching the donor animal with Pilobolus spores and kept at 16 +/- 2 degrees C. Most larvae were collected between the 5th and the 8th day of culturing during which period fructification and sporangium discharge also peaked. The sporangia and the adhering larvae were collected in Petri dishes inserted between the faecal mass and a light source. All...
Bienert-Zeit A, Gietz C, Staszyk C, Kietzmann M, Stahl J, Ohnesorge B.To monitor concentrations of sulfadimidine in the paranasal sinus mucosa (PSM) of unsedated horses following IV administration of trimethoprim-sulfadimidine via in vivo microdialysis. Methods: 10 healthy adult horses. Methods: Concentric microdialysis probes were implanted into the subepithelial layers of the frontal sinus mucosa of standing sedated horses. Four hours after implantation, trimethoprim-sulfadimidine (30 mg/kg) was administered IV every 24 hours for 2 days; dialysate and plasma samples were collected at intervals during that 48-hour period and analyzed for concentrations of sulfa...
Simon V, Dyson SJ.We compared the radiographic and scintigraphic findings in the third carpal bone of horses performing different work disciplines and investigated their relationship with lameness. Horses had undergone carpal radiography including acquisition of a dorsoproximal-dorsodistal oblique (DPr-DDiO) image of the distal row of carpal bones and/or scintigraphic examination of the carpi. Cause of lameness, breed, age, and work discipline were recorded. Increased opacity in the third carpal bone was graded, ratio of radiopharmaceutical uptake calculated objectively, and increased radiopharmaceutical uptake...
Morandi F, Frank N, Avenell J, Daniel GB.99mTc-mebrofenin is used in humans and small animals to assess hepatic function. This study was undertaken to measure hepatic clearance of 99mTc-mebrofenin in healthy horses and to determine whether feed deprivation and increased serum total bilirubin (TBIL) concentration alter 99mTc-mebrofenin clearance. Plasma clearance of 99mTc-mebrofenin was determirned in 7 healthy horses at 0, 48, and 96 hours of feed withholding. Serum TBIL and nonesterified fatty acid (NEFA) concentrations were measured every 24 hours. 99mTc-mebrofenin (4.16 +/- 0.62 mCi, mean +/- SD) was injected into a jugular vein, ...
McClintock SA, Hutchins DR, Laing EA, Brownlow MA.Six adult horses with normal blood gas values, normal thoracic radiographs and free from overt signs of respiratory disease were confined in flotation tanks for periods from one to seven weeks. With one exception, they all coughed, had a variable amount of nasal discharge and, at autopsy, showed cranio-ventral alterations to their lungs which were characterised by patchy irregular areas of absorption atelectasis with or without an inflammatory reaction and an accompanying alveolar emphysema.
Iff I, Mosing M, Lechner T, Moens Y.To determine the usefulness of an acoustic device to confirm correct placement of extradural needles in horses. Methods: Prospective experimental study. Methods: Twelve adult healthy horses weighing between 434 and 640 kg. Methods: Horses were sedated, placed in stocks and subjected to caudal extradural anaesthesia using lidocaine 2%. For extradural puncture an 18 gauge Tuohy needle connected to an acoustic device via an electronic pressure transducer was used. This device allowed recording of the extradural pressure profile and the transformation of pressure changes into an audible signal. Ex...
Heinze H, Klug E.Clinical tests with synthetic gonadotrophin-releasing hormone (Hoechst) were made during the breeding seasons of 1973 and 1974, using 128 mares injected with 1-0 to 4-0 mg of the substance intramuscularly. The mares were placed in one of five groups based on ovarian condition determined by clinical evidence. Some success was obtained in the induction of ovulation in mares with inactive and sub-normally active ovaries and in a small group having cystic ovaries. A large proportion of mares having a mature follicle responded within 48 hr, but others with atretic follicles failed to respond. The u...
Grøndahl AM, Jansen JH, Teige J.Fifty-six tarsocrural joints and 94 metatarsophalangeal joints were examined, at necropsy, from horses aged < or = 2 years. Osteochondral fragments at the cranial aspect of the intermediate ridge of the distal part of the tibia were seen in six horses, and at the proximoplantar aspect of the proximal phalanx in seven horses. Defects in the proximoplantar aspect of the proximal phalanx without osteochondral fragments were seen in a further two horses. Inflammatory and degenerative changes were not observed in any of the joints examined. From the incidence and natural course of these fragment...
Brama PA, Barneveld A, Karssenberg D, Van Kampen GP, van Weeren PR.A recently developed indenter system that aims at determination of local structural properties of the cartilage surface was evaluated for suitability in the horse. To this aim, maximum indenter force was measured of the articular surface and related to biochemical characteristics of the cartilage at different sites of the distal metacarpal bone (MC). Significant topographical variation exists in structural properties of the articular surface of the MC. The dorsal margin showed a significantly lower maximum indenter force than more centrally located areas, indicating an increased compliance und...
Giguère S, Macpherson ML, Benson SM, Cox S, McNaughten JW, Pozor MA.Pregnancy induces several physiologic changes that might impact the bioavailability, distribution, metabolism, and excretion of drugs. The objective of this study was to determine the effects of pregnancy on the disposition of oral firocoxib in mares. Seven pony mares received oral firocoxib paste at a dose of 0.1 mg/kg during late pregnancy and again 12 to 33 days postpartum. Firocoxib concentrations were measured in plasma by HPLC with ultraviolet detection. Maximum plasma concentrations were significantly lower in pregnant (50.0 ± 21.8 ng/mL) than in postpartum (73.7 ± 25.6 ng/mL) mares. ...
Brown CM, Holmes JR.In horses experimental right and left heart catheterization using a catheter with two microtransducers 9 cm apart, usually in a transvalval position produced pressure and sound artifacts that confounded the diagnosis. Most were probably due to malpositioning resulting in movement through a valve during recording or impingement on the valve cusps or the chordae tendineae or lodgement in the apex of the heart. The recognition of these artifacts is particularly important in studies of large animals in which catheter siting cannot be monitored by radiography.
Calvo-Santesmases A, Manso-Díaz G, Fores P, López-Sanromán J.Alpha-2-adrenergic drugs, such as detomidine, are commonly used to sedate lame horses during examination. However, the use of these drugs should be minimized, as they have numerous side-effects, like ataxia. Therefore, we wanted to test the effects, on the locomotor pattern, of low doses of detomidine (0.003 mg/kg). Six horses were sedated with 0.003 mg/kg of detomidine and compared with the same horses administered a saline solution. Using a triaxial accelerometer, data of kinetic, coordination and energetic locomotor parameters and the degree of sedation were collected. The effects were moni...
Simpson CF, Taylor WJ, Kitchen H.Four splenectomized Welsh ponies were infected with Babesia equi. Two ponies were treated with imidocarb dipropionate, and two were not treated. By light microscopic examination, 1% to 2% of the parasitized erythrocytes of treated ponies contained crystalline inclusions. The crystals were rectangular, diamond, or burr shaped. They occupied most of the erythrocytic cytoplasm, and, as a result, the remainder of the pale staining cytoplasm was inconspicuous in Wright-Giemsa-stained blood smears. The size and shape of intraerythrocytic inclusions varied when examined by electron microscopy, but in...
Schryver HF, Hintz HF, Lowe JE.Absorption excretion and tissue distribution of stable Zn and 65Zn in mature ponies were studied in three experiments. In the first experiment, the metabolism of stable, dietary Zn and intravenously administered 65Zn was studied in three ponies in a 3 X 3 Latin square design. The ponies were fed a corn and beet pulp diet containing 35 mg Zn/kg or the same diet with 250 or 520 mg of supplemental Zn as ZnO. The ponies absorbed and retained more stable Zn when fed 250 mg of supplemental Zn that when fed the basal diet alone or the basal diet plus 520 mg of supplemental Zn. The ponies retained mor...
Manohar M, Thurmon JC, Tranquilli WJ, Shawley RV, Froelich P.A technique was developed for long-term catheterization of the coronary sinus in calves and ponies. A catheter with a 10 to 12 cm-long stiff segment was implanted via right lateral thoracotomy. Catheters were kept patent up to 10 weeks after the surgical procedure. At that time, location of the catheter tip was confirmed both by determining oxygen tension of the anaerobically sampled blood and by radiography. Base-line values of oxygen venous blood of non-anesthetized calves and ponies are reported.
Within the veterinary world, data regarding the surgical management of hypospadias is lacking. Reports within equines have documented resective phallectomy procedures rather than urethral reconstruction. This case report documents the first ever urethroplasty for an equine hypospadias, performed by a consultant paediatric surgeon. The urethroplasty was achieved by applying the same surgical principles mastered from paediatric urology to a horse. The indication for surgery was contact dermatitis of the hind-leg, which impaired the thoroughbred foal's racing potential. Methods: A single stage ur...
Madsen LM, Gutierrez-Nibeyro SD, Stewart MC, McCoy AM, Schaeffer DJ.To determine the stance duration and ground reaction forces (GRF) of horses with deep digital flexor (DDF) tendinopathy at the level of the foot and compare the stance duration and GRF to those of clinically sound horses. Unassigned: Prospective clinical study. Unassigned: Sixteen horses (seven horses with bilateral forelimb lameness, four horses with unilateral forelimb lameness, and five horses with no lameness). Unassigned: Analyses of kinetic variables were performed on both forelimbs from sound horses and horses diagnosed with chronic DDF tendinopathy. Stance duration and longitudinal and...